In prior art, procedures are known in which the fabrics used in a paper machine or equivalent, such as wires and/or felts, are washed with various chemicals to extend their service life. The washing is performed either continuously while the machine is running or periodically e.g. during down time.
An essential factor in the washing of the fabrics is the accuracy of dosage of chemicals. If an overdose of chemicals is used, this may have adverse effects on the quality of the paper being produced and/or to the runnability of the paper machine. In addition, the operating costs are increased because the chemicals are relatively expensive. On the other hand, if too small amounts of chemicals are used, the washing result will be impaired.